Coverage of climate change in introductory biology textbooks, 1970–2019

fuel production and its importance to textbook publishers (known as The Texas Effect), mini- mizing content on climate change could reduce problems in textbook adoption [26]. Publish- ers often diminish controversial issues to tailor textbook content, reflecting public concerns [27]. Due to the history of biology textbooks and their inclusion of controversial topics toward the rear of the books, societal concerns may have contributed to the stagnancy of climate change coverage. Second, the amount of content may have decreased as authors or publishers grew con- cerned about the negative psychological impacts of a focus on climate change. Extreme weather events, uncertainty, and guilt can trigger anxiety, depression, grief, trauma, and sui- cidal ideation [28]. However, our analysis of the topics addressed within the climate change passage shows an emphasis on the effects and a decline in solutions, which would increase feel- ings of hopelessness and helplessness in students. Therefore, we refute the contribution of “cli- mate despair” on the stagnancy in climate change content. Finally, textbook authors may weigh topics more heavily if the subjects reflect their research interests or expertise. There has been a notable and dramatic decrease in the number of organ- ismal- and ecological-based college classes required for biologists, as well as a decline in natural history careers, grants, and research among faculty [29, 30]. This would result in fewer faculty with expertise in ecology or organismal biology, and more authors of recent biology textbooks

focused on cellular and molecular biology. To check the legitimacy of this claim, we searched for the research focus or dissertation topic of the first two authors from each textbook pub- lished in the 1990s, at the height of climate change coverage, and in the 2010s, with the drop in climate change coverage. In the 1990s, nine authors (53% of those with scientific foci) studied organismal biology or ecology, five studied physiology, and three (18%) studied cell or molecu- lar biology. There were an additional eight authors focused on science education or science writing. In the 2010s, five authors (45%) studied organismal biology or ecology, one studied Fig 7. Types of figures presenting data in textbook passages about climate change. Early textbooks contained no data visuals. Most textbooks published in the 1990s included a graph showing carbon dioxide levels and Earth temperatures until 2010. Recent textbooks include more diversity in data figures, such as photographs of glacier retreat and maps of species movements. https://doi.org/10.1371/journal.pone.0278532.g007 PLOS ONE Climate change in biology textbooks, 1970–2019 PLOS ONE | https://doi.org/10.1371/journal.pone.0278532 December 21, 2022 11 / 16